(semantics) The property of terms of having a single meaning; absence of ambiguity. / (literary) singularity

(Indo-European studies) a proposed branch within the Indo-European language family, of which the Hellenic and Indo-Iranian branches are sub-branches.

(biology) wedge-shaped. / (botany) wedge-shaped, with the narrow part at the base. / (botany) having straight, or almost straight sides meeting at the apex or base.

A surname from Italian.